Yogg+1 and General are very easy hard modes on 10man.
My guild and I, had 2 tries on General HM, 2 hours on Yogg+1 due to retards we called it a night. The day after we took it down on the 2nd try.
Mimiron is a bitch tho', get an even balance of melee and ranged.
When it comes to healers, it doesn't really matter any more which combo you take. But priests are really kickass here.
As for tanks, we have a death knight, since they have awesome cooldowns, and alot of them. We normally have a dps warrior tanking the head in ph3 and ph4.
Today we had a warlock tanking it, it went fine, tho' abit chaotic in ph4 if you ask me.
I hope you can use this, it really worked out for us.